Unfortunately this doesn't seem to be a license expiration issue - I've had those before, and they display a different dialog. I think the expiration is hard-coded into the binary.

It makes sense that JetBrains wouldn't want ropey EAPs running forever, so expiring them is probably a good idea, and a 50-day expiration is plenty of time for developers to install a newer version. Unfortunately there's nothing to replace the expired build.